Stacked semiconductor die assemblies with partitioned logic and associated systems and methods

ABSTRACT

Stacked semiconductor die assemblies having memory dies stacked between partitioned logic dies and associated systems and methods are disclosed herein. In one embodiment, a semiconductor die assembly can include a first logic die, a second logic die, and a thermally conductive casing defining an enclosure. The stack of memory dies can be disposed within the enclosure and between the first and second logic dies.

TECHNICAL FIELD

The disclosed embodiments relate to semiconductor die assemblies and tomanaging heat within such assemblies. In particular, the presenttechnology relates to die assemblies having memory dies stacked betweenpartitioned logic dies.

BACKGROUND

Packaged semiconductor dies, including memory chips, microprocessorchips, and imager chips, typically include a semiconductor die mountedon a substrate and encased in a plastic protective covering. The dieincludes functional features, such as memory cells, processor circuits,and imager devices, as well as bond pads electrically connected to thefunctional features. The bond pads can be electrically connected toterminals outside the protective covering to allow the die to beconnected to higher level circuitry.

Semiconductor manufacturers continually reduce the size of die packagesto fit within the space constraints of electronic devices, while alsoincreasing the functional capacity of each package to meet operatingparameters. One approach for increasing the processing power of asemiconductor package without substantially increasing the surface areacovered by the package (i.e., the package's “footprint”) is tovertically stack multiple semiconductor dies on top of one another in asingle package. The dies in such vertically-stacked packages can beinterconnected by electrically coupling the bond pads of the individualdies with the bond pads of adjacent dies using through-silicon vias(TSVs).

The heat generated by the individual dies in vertically stacked diepackages is difficult to dissipate, which increases the operatingtemperatures of the individual dies, the junctions therebetween, and thepackage as a whole. This can cause the stacked dies to reachtemperatures above their maximum operating temperatures (T_(max)) inmany types of devices and especially as the density of the dies in thepackage increases.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a semiconductor die assemblyconfigured in accordance with an embodiment of the present technology.

FIG. 2A is an isometric view illustrating a temperature profile of a HMCassembly during operation, and FIG. 2B is a an isometric viewillustrating a temperature profile of a HMC assembly in accordance withan embodiment of the present technology.

FIG. 2C is an isometric view illustrating a semiconductor die assemblyconfigured in accordance with another embodiment of the presenttechnology.

FIG. 3 is a cross-sectional view of a semiconductor die assemblyconfigured in accordance with another embodiment of the presenttechnology.

FIG. 4 is a schematic view of a semiconductor die assembly havingintegrated circuit components configured in accordance with anembodiment of the present technology.

FIG. 5 is a flow diagram illustrating a method for operating asemiconductor die assembly in accordance with an embodiment of thepresent technology.

FIG. 6 is a cross-sectional view of a semiconductor die assemblyconfigured in accordance with another embodiment of the presenttechnology.

FIG. 7 is a schematic view of a system that includes a semiconductor dieassembly configured in accordance with embodiments of the presenttechnology.

DETAILED DESCRIPTION

Specific details of several embodiments of stacked semiconductor dieassemblies having memory dies stacked between partitioned logic dies andassociated systems and methods are described below. The term“semiconductor die” generally refers to a die having integrated circuitsor components, data storage elements, processing components, and/orother features manufactured on semiconductor substrates. For example,semiconductor dies can include integrated circuit memory and/or logiccircuitry. Semiconductor dies and/or other features in semiconductor diepackages can be said to be in “thermal contact” with one another if thetwo structures can exchange energy through heat. A person skilled in therelevant art will also understand that the technology may haveadditional embodiments, and that the technology may be practiced withoutseveral of the details of the embodiments described below with referenceto FIGS. 1-7.

As used herein, the terms “vertical,” “lateral,” “upper” and “lower” canrefer to relative directions or positions of features in thesemiconductor die assemblies in view of the orientation shown in theFigures. For example, “upper” or “uppermost” can refer to a featurepositioned closer to the top of a page than another feature. Theseterms, however, should be construed broadly to include semiconductordevices having other orientations.

FIG. 1 is a cross-sectional view of a semiconductor die assembly 100(“assembly 100”) configured in accordance with an embodiment of thepresent technology. As shown, the assembly 100 includes a first logicdie 102 a, a second logic die 102 b (collectively “logic dies 102”), anda plurality of memory dies 103 arranged in a stack 105 (“memory diestack 105”) between the logic dies 102. The first logic die 102 a iselectrically coupled to a package substrate 120 by an interposer 122.The interposer 122 can include, for example, a semiconductor die, adielectric spacer, and/or other suitable substrate having electricalconnectors (e.g., vias, metal traces, etc.) connected between theinterposer 122 and the package substrate 120. The package substrate 120can include, for example, an interposer, a printed circuit board, orother suitable substrate connected to package contacts 124 (e.g., bondpads) and electrical connectors 125 (e.g., solder bumps) thatelectrically couple the assembly 100 to external circuitry (not shown).In some embodiments, the package substrate 120 and/or the interposer 122can be configured differently. For example, in some embodiments theinterposer 122 can be omitted and the first logic die 102 a can bedirectly connected to the package substrate 120.

The first and second logic dies 102 a and 102 b are coupled to aplurality of through-stack interconnects 130 extending through thememory die stack 105. In the illustrated embodiment of FIG. 1, thethrough-stack interconnects 130 are shown as generally vertical,singular structures for purposes of illustration. However, each of thethrough-stack interconnects 130 can be composed of a combination ofvertically and/or laterally arranged conductive elements interconnectedto one another throughout the memory die stack 105. For example, each ofthe through-stack interconnects 130 can include an arrangement ofinterconnected conductive pillars, vias, through-die vias, solder bumps,metal traces, etc.

The assembly 100 further includes a thermally conductive casing 110 atleast partially enclosing the second logic die 102 b and the memory diestack 105 within an enclosure (e.g., a cavity). In the illustratedembodiment, the casing 110 includes a cap portion 112 and a wall portion113 attached to or integrally formed with the cap portion 112. The capportion 112 can be attached to a back side portion 106 of the secondlogic die 102 b by a first interface material 114 a (e.g., an adhesive).The wall portion 113 can extend vertically away from the cap portion 112and be attached to a peripheral portion 107 of the first logic die 102 a(known to those skilled in the art as a “porch” or “shelf) by a secondinterface material 114 b (e.g., an adhesive). In addition to providing aprotective covering, the casing 110 also provides a heat spreader toabsorb and dissipate thermal energy away from the logic and memory dies102 and 103. The casing 110 can accordingly be made from a thermallyconductive material, such as nickel, copper, aluminum, ceramic materialswith high thermal conductivities (e.g., aluminum nitride), and/or othersuitable thermally conductive materials.

In some embodiments, the first interface material 114 a and/or thesecond interface material 114 b can be made from what are known in theart as “thermal interface materials” or “TIMs”, which are designed toincrease the thermal contact conductance at surface junctions (e.g.,between a die surface and a heat spreader). TIMs can includesilicone-based greases, gels, or adhesives that are doped withconductive materials (e.g., carbon nano-tubes, solder materials,diamond-like carbon (DLC), etc.), as well as phase-change materials. Insome embodiments, for example, the thermal interface materials can bemade from X-23-7772-4 TIM manufactured by Shin-Etsu MicroSi, Inc. ofPhoenix, Ariz., which has a thermal conductivity of about 3-4 W/m° K. Inother embodiments, the first interface material 114 a and/or the secondinterface material 114 b can include other suitable materials, such asmetals (e.g., copper) and/or other suitable thermally conductivematerials.

The logic dies 102 and/or the memory dies 103 can be at least partiallyencapsulated in a dielectric underfill material 116. The underfillmaterial 116 can be deposited or otherwise formed around and/or betweensome or all of the dies of the assembly 100 to enhance the mechanicalconnection between the dies and/or to provide electrical isolationbetween, e.g., interconnects or other conductive structures between thedies. The underfill material 116 can be a non-conductive epoxy paste(e.g., XS8448-171 manufactured by Namics Corporation of Niigata, Japan),a capillary underfill, a non-conductive film, a molded underfill, and/orinclude other suitable electrically-insulative materials. In severalembodiments, the underfill material 116 can be selected based on itsthermal conductivity to enhance heat dissipation through the dies of theassembly 100. In some embodiments, the underfill material 116 can beused in lieu the first interface material 114 a and/or the secondinterface material 114 b to attach the casing 110 to the first logic die102 a and/or the second logic die 102 b.

The logic and memory dies 102 and 103 can each be formed from asemiconductor substrate, such as silicon, silicon-on-insulator, compoundsemiconductor (e.g., Gallium Nitride), or other suitable substrate. Thesemiconductor substrate can be cut or singulated into semiconductor dieshaving any of variety of integrate circuit components or functionalfeatures, such as dynamic random-access memory (DRAM), staticrandom-access memory (SRAM), flash memory, other forms of integratedcircuit devices, including memory, processing circuits, imagingcomponents, and/or other semiconductor devices. In selected embodiments,the assembly 100 can be configured as a hybrid memory cube (HMC) inwhich the memory dies 103 provide data storage (e.g., DRAM dies) and thelogic dies 102 collectively provide memory control (e.g., DRAM control)within the HMC. In some embodiments, the assembly 100 can include othersemiconductor dies in addition to and/or in lieu of one or more of thelogic dies 102 and the memory dies 103. For example, such semiconductordies can include integrated circuit components other than data storageand/or memory control components. Further, although the assembly 100includes ten dies stacked on the interposer 122, in other embodimentsthe assembly 100 can include fewer than ten dies (e.g., six dies) ormore than ten dies (e.g., twelve dies, fourteen dies, etc.). Forexample, in one embodiment, the assembly 100 can include two logic diesstacked on top of four memory dies and a single logic die stacked belowthe four memory dies. Also, in various embodiments, the logic dies 102and the memory dies 103 can have different sizes. For example, in someembodiments the first logic die 102 a can have the same footprint thanthe memory die stack 105 and/or the second logic die 102 b can have asmaller or larger footprint than the memory die stack 105.

In general, the heat produced by a logic die can be significantlygreater than the heat collectively produced by memory dies. Forinstance, a logic die in a conventional HMC assembly can consume 80% ofthe overall power during operation. A conventional semiconductor dieassembly typically includes a single logic die positioned toward thebottom of the assembly. This means that during operation heat from thelogic die must transfer through the memory dies en route to the casingof the assembly. Because the heat transfers through the memory dies,this increases the overall temperature of the assembly. FIG. 2A, forexample, is an isometric view illustrating a temperature profile of aHMC assembly 290 during operation. As shown, the HMC assembly 290includes stacked memory dies 204 and a single, underlying logic die 201.During operation, the high temperature of the logic die 201 concentratesthermal energy toward the bottom of the assembly 290. For example, thelogic die 201 has a maximum operating temperature of about 111° C.,while the memory dies 204 have a maximum operating temperature of about105° C. This concentration of heat can cause the logic die 201 as wellas adjacent memory dies 204 to exceed their maximum operatingtemperature (T_(max)). This can especially be the case for newergeneration HMC assemblies, which can have a logic core power of, e.g.,about 14 W (vs., e.g., about 4 W for earlier generation HMC assemblies).

Semiconductor die assemblies configured in accordance with embodimentsof the present technology are expected to reduce the flow of heatthrough the memory dies. FIG. 2B, for example, is an isometric viewillustrating a temperature profile of a HMC assembly 200 duringoperation in accordance with the present technology. The HMC assembly200 includes a stack of memory dies 203 disposed between a first logicdie 202 a and a second logic die 202 b. As shown, the first logic die202 a dissipates a majority of its heat toward a peripheral portion 207.For example, the peripheral portion 207 can dissipate heat directly tothe wall portion 113 of the casing 110 (FIG. 1). The second logic die202 b, on the other hand, dissipates a majority of its heat toward thetop of the assembly. For example, the second logic die 202 b candissipate heat directly to the cap portion 112 of the casing 110 (FIG.1). As a result, the maximum temperature of the first logic die 202 a islower than the maximum temperature of the logic die 201 of the HMCassembly 290 (e.g., 96° C. vs. 111° C.). Also, the maximum temperatureof the memory dies 203 is lower than the maximum operation temperatureof the memory dies 204 (e.g., 91° C. vs. 96° C.). As a result, the logicand memory dies 202 and 203 of the HMC assembly 200 can operate within amore acceptable temperature range and below maximum temperaturespecifications.

In general, the logic dies of a semiconductor die assembly can includeintegrated circuit components having any of a variety of arrangementsfor dissipating heat throughout a semiconductor die assembly. FIG. 2C,for example, shows a semiconductor die assembly 260 having a logic die202 c below the stack of memory dies 203 and a logic die 202 d on top ofthe stack of memory dies 203. The logic die 202 c can include firstintegrated circuit components 240 a (shown schematically) concentratedtoward the periphery of the logic die 202 c, and the logic die 202 d caninclude second integrated circuit components 240 b (shown schematically)formed across substantially the entire logic die 202 d. In anotherembodiment, the second integrated circuit components 240 b can be offsetfrom the periphery of the logic die 202 d and disposed more centrally(as shown by the superimposed footprint 227). In various embodiments,integrated circuit components can also be configured to producedifferent amounts of heat. For example, the integrated circuitcomponents of a top-most logic die can produce more than 50% of thelogic-related heat (e.g., about 75% or more of the heat), while thebottom-most logic die can produce less than 50% of the logic-relatedheat (e.g., about 25% or less of the heat). Alternately, the integratedcircuit components of the top-most logic die can produce less heat thanthe circuit components of the bottom-most logic die.

FIG. 3 is a cross-sectional view of a semiconductor die assembly 300(“assembly 300”) configured in accordance with another embodiment of thepresent technology. The assembly 300 can include features generallysimilar to those of the assembly 100 described in detail above. Forexample, the assembly 300 can include the memory die stack 105positioned between the logic dies 102. In the illustrated embodiment ofFIG. 2, the first logic die 102 a, the second logic die 102 b, and eachof the memory dies 103 are electrically coupled to one another by aplurality of electrical connectors or interconnects 332 (e.g., copperpillars, solder bumps, conductive traces, contact pads, etc.). The firstlogic die 102 a and the individual memory dies 103 can each include aplurality of through-die interconnects 334 (e.g., through-substratevias, TSVs, etc.) that are coupled on opposite sides to theinterconnects 332. The interconnects and the through-die interconnects332 and 334 can be formed from various types of conductive materials(e.g., metallic materials), such as copper, nickel, aluminum, etc. Insome embodiments, the conductive materials can include solder (e.g.,SnAg-based solder), conductor-filled epoxy, and/or other electricallyconductive materials. In selected embodiments, for example, theinterconnects 332 can be copper pillars, whereas in other embodimentsthe interconnects 332 can include more complex structures, such asbump-on-nitride structures. In other embodiments, the interconnects 332can be replaced with other types of materials or structures, such as aconductive paste.

In one aspect of this embodiment, the second logic die 102 b can beformed without through-die interconnects because it is disposed towardthe top of the assembly 100 rather than the bottom of the assembly. Forexample, conventional semiconductor die packages have a single logicdisposed between the package substrate and the memory die stack. Thisarrangement can require the logic die to have through-die interconnectsto electrically connect the package substrate with the memory die stack.This arrangement can also require the logic die to be thin to reduce thevertical length and the aspect ratio of the through-die interconnects.For example, logic dies (or the substrates used to form the logic dies)can be thinned to size by backgrinding, etching, and/or chemicalmechanical polishing (CMP). One advantage, therefore, with having thesecond logic die 102 b at the top of the assembly 100 is that the secondlogic die 102 b can be formed with fewer manufacturing steps than thefirst logic die 102 a. For example, the second logic die 102 b can beformed without substrate thinning, through-hole etching, and metaldeposition processes for forming through-die interconnects. In severalembodiments, the second logic die 102 b can have a thickness in therange of about 300 μm to about 1000 μm (e.g., 350 μm) and the other diesin the assembly 100 can have a thickness in the range of about 50 toabout 200 μm (e.g., 100 μm).

In another aspect of this embodiment, the second logic die 102 bincludes a bulk portion 329 of the semiconductor substrate that wouldordinarily be removed from the second logic die 102 b when formingthrough-die interconnects. In several embodiments, the bulk portion 329can facilitate heat conduction away from the assembly 100 and throughthe cap portion 112 of the casing 120. In another embodiment, the casing120 can be omitted from the assembly 300 such that an an outermostsurface 326 of the assembly 100 is exposed. In an alternate embodiment,the outermost surface 326 can be covered with the underfill material 116and/or another material (e.g., an encapsulant of a package casing).

In addition to electrical communication, the interconnects and thethrough-die interconnects 332 and 334 can serve as conduits throughwhich heat can be transferred away from the memory die stack 105 andtoward the casing 110. In some embodiments, the assembly 100 can alsoinclude a plurality of thermally conductive elements or “dummy elements”(not shown) positioned interstitially between the interconnects 332 tofurther facilitate heat transfer away from the logic dies 102 and thememory dies 103. Such dummy elements can be at least generally similarin structure and composition as the interconnects 332 except that theyare not electrically coupled to the logic dies 102 and the memory dies103.

In the illustrated embodiment, a plurality of through-stackinterconnects 330 couple bond pads 308 of the first logic die 102 a withcorresponding bond pads 309 of the second logic die 102 b. As discussedabove, the through-stack interconnects 330 can each be composed of acollective portion of the interconnects 332 and the through-dieinterconnects 334. In some embodiments, a portion 339 of thethrough-stack interconnects 330 can be functionally isolated from thefirst logic die 102 a. For example, the portion 339 of the through-stackinterconnects 330 can be connected to “dummy” contact pads 331 at thefirst logic die 102 a that are functionally isolated from the integratedcircuit components (not shown) of the first logic die 102 a.

FIG. 4 is a schematic view of a semiconductor die assembly (“assembly400”) having integrated circuit components configured in accordance withan embodiment of the present technology. The assembly 400 can includefeatures generally similar to those of the die assemblies described indetail above. For example, the assembly 400 can include the memory diestack 105 disposed between the first logic die 102 a and a second logicdie 102 b. In the illustrated embodiment, the first logic die 102 aincludes communication components 440 coupled to the package contacts124 of the package substrate 120 (FIG. 1) The second logic die 102 b caninclude memory controller components 442 (“memory controller 442”)coupled to the communication components 440 by one or more firstthrough-stack interconnects (schematically represented by double-sidedarrow 430 a). Each of the memory dies 103 can include a plurality ofmemory cells (not shown) arranged in one or more arrays and/or memoryblocks of memory (“memory 444”). The memory 444 of the individual memorydies 103 is coupled to the memory controller 442 by one or more secondthrough-stack interconnects (schematically represented by double-sidedarrow 430 b).

In one aspect of this embodiment, the communication components 440 arearranged toward the outer periphery of the first logic die 102 a todissipate heat to the wall portion 113 of the casing 110 (FIG. 1). Thememory controller 442, on the other hand, is positioned at the top ofthe assembly 100 to dissipate heat to the cap portion 112 of the casing110 (FIG. 1). In some embodiments, however, the communication components440 and/or the memory controller 442 can be positioned differentlywithin the assembly 400. For example, in several embodiments thecommunication components 440 can be located at more than two sides ofthe memory die stack 105. In other embodiments, the communicationcomponents 440 can be located at a single side of the memory die stack105. Further, in certain embodiments, the communication components 440can extend beneath the memory die stack 105.

In several embodiments, the first logic die 102 a and/or the secondlogic die 102 b can include additional and/or alternative integratedcircuit components. For example, in the illustrated embodiment, thefirst logic die 102 a includes additional circuit components 441 beneaththe memory die stack 105 (e.g., power distribution components, clockcircuits, etc.). In several embodiments, the additional circuitcomponents 441 can have lower operating temperatures than thecommunication components 440. In one embodiment, the additional circuitcomponents 441 can be coupled to the second logic die 102 b by thirdthrough-stack interconnects (schematically represented by double-sidedarrow 430 c). In another embodiment, the additional circuit components441 can also be coupled to the second logic die 102 b by the firstthrough-stack interconnects 430 a and/or the second through-stackinterconnects 430 b. Alternately, the first through-stack interconnects430 a and/or the second through-stack interconnects 430 b can bededicated circuit paths that are not connected to the additional circuitcomponents 441. Moreover, although not illustrated in the Figures forpurposes of clarity, each of the communication components 440, thememory controller 442, and/or the memory 444 can include a variety ofcircuits elements. For example, these circuit components can includemultiplexers, shift registers, encoders, decoders, driver circuits,amplifiers, buffers, registers, filters (e.g., low pass, high pass,and/or band pass filters), etc.

FIG. 5 is a flow diagram illustrating a method 570 for operating asemiconductor die assembly in accordance with an embodiment of thepresent technology. In several embodiments, the method 570 can beemployed for operating the die assemblies described in detail above. Atblock 572, the communication components 440 (FIG. 3) receive an inputstream of serial data S_(I) (“serial input S_(I)”) from the packagecontacts 124 (FIG. 1). The serial input S_(I) can contain, for example,data and instructions to store the data. In addition or alternately, theserial input S_(I) can contain instructions to read data and/or erasedata. At block 574, the communication components 440 deserializes theserial input S_(I) into a plurality of input streams P_(I1)-P_(IX). Inseveral embodiments, the communication components 440 can include one ormore serializer/deserializer circuits (known to those skilled in the artas “SerDes” circuits) configured to convert a serial flow of data into aparallel flow of data (and vice versa). For example,serializer/deserializer circuits can both produce and convert paralleldata flows having multiple signal components (e.g., four componentsignals, eight component signals, sixteen component signals, etc.).

At block 576, the memory controller 442 (FIG. 3) receives the inputstreams P_(I1)-P_(Ix) over the first through-stack interconnects. Forexample, the memory controller can receive the first input stream P_(I1)over a portion of the through-stack interconnects 130 (FIG. 1) whilesimultaneously or near simultaneously receiving the other input streamsP_(I2)-P_(IX) over another portion of the through-stack interconnects130. At block 578, the memory controller 442 processes the input streamsP_(I1)-P_(IX) and then selects and accesses certain memory via thesecond through-stack interconnects. For example, the memory controller442 can select and access the memory 444 (FIG. 3) of one or more of thememory dies 103 by encoding instructions along with a memory address toretrieve, store, and/or erase data.

At block 580, the memory controller 442 processes a response receivedfrom the selected memory into a plurality of output streamsP_(O1)-P_(OX). The response can include, for example, requested data, aconfirmatory response, and/or other information (e.g., an error responseif data cannot be read or written) from the selected memory. At block582, the communication components 440 receive the plurality of outputstreams P_(O1)-P_(OX) over at least a portion of the first through-stackinterconnects. At block 584, the communication components 440 thenserialize the output streams P_(O1)-P_(OX) into an output serial datastream S_(O) (“serial output S_(O)”) that can be output to the packagecontacts 124.

FIG. 6 is a cross-sectional view of a semiconductor die assembly 600(“assembly 600”) configured in accordance with another embodiment of thepresent technology. The assembly 600 can include features generallysimilar to those of the die assemblies described in detail above. Forexample, the assembly 600 includes the memory die stack 105 and thesecond logic die 102 b enclosed within the casing 110. In theillustrated embodiment of FIG. 6, however, the first logic die 102 a isnot attached to the memory die stack 105. Rather, the first logic die102 a is mounted to a different location on a support substrate 620(e.g., a printed circuit board). Accordingly, the first logic die 102 ais electrically coupled to the second logic die 102 b throughcommunication paths that extend through the support substrate 620, theinterposer 122, and the through-stack interconnects 130. In thisembodiment, the heat produced by the first logic die 102 a does not doesdissipate through the memory die stack 105 or the second logic die 102 band thus the memory dies 103 and the second logic die 102 b can havelower operating temperatures.

Any one of the stacked semiconductor die assemblies described above withreference to FIGS. 1-6 can be incorporated into any of a myriad oflarger and/or more complex systems, a representative example of which issystem 790 shown schematically in FIG. 7. The system 790 can include asemiconductor die assembly 700, a power source 792, a driver 794, aprocessor 796, and/or other subsystems or components 798. Thesemiconductor die assembly 700 can include features generally similar tothose of the stacked semiconductor die assemblies described above. Theresulting system 790 can perform any of a wide variety of functions,such as memory storage, data processing, and/or other suitablefunctions. Accordingly, representative systems 790 can include, withoutlimitation, hand-held devices (e.g., mobile phones, tablets, digitalreaders, and digital audio players), computers, and appliances.Components of the system 790 may be housed in a single unit ordistributed over multiple, interconnected units (e.g., through acommunications network). The components of the system 790 can alsoinclude remote devices and any of a wide variety of computer readablemedia.

From the foregoing, it will be appreciated that specific embodiments ofthe technology have been described herein for purposes of illustration,but that various modifications may be made without deviating from thedisclosure. For example, although many of the embodiments of thesemiconductor dies assemblies are described with respect to HMCs, inother embodiments the semiconductor die assemblies can be configured asother memory devices or other types of stacked die assemblies. Certainaspects of the new technology described in the context of particularembodiments may also be combined or eliminated in other embodiments.Moreover, although advantages associated with certain embodiments of thenew technology have been described in the context of those embodiments,other embodiments may also exhibit such advantages and not allembodiments need necessarily exhibit such advantages to fall within thescope of the technology. Accordingly, the disclosure and associatedtechnology can encompass other embodiments not expressly shown ordescribed herein.

1. A semiconductor die assembly, comprising: a first logic die; a secondlogic die; and a stack of memory dies disposed between the first andsecond logic dies.
 2. The die assembly of claim 1 wherein: the firstlogic die includes a memory controller; and the second logic dieincludes a communication component.
 3. The die assembly of claim 2wherein the communication component includes a serial/deserializercircuit.
 4. The die assembly of claim 1, further comprising a thermallyconductive casing defining an enclosure, wherein the stack of memorydies are disposed within the enclosure.
 5. The die assembly of claim 4wherein the second logic die is disposed between the thermallyconductive casing and the stack of memory dies, and wherein the secondlogic die is electrically coupled to the first logic die via the stackof memory dies.
 6. The die assembly of claim 5 wherein the second logicdie includes a semiconductor substrate, and wherein the semiconductorsubstrate does not include any through-die interconnects extendingthrough the semiconductor substrate.
 7. The die assembly of claim 1wherein: the first logic die has a first thickness; and the second logicdie has a second thickness that is less than the first thickness.
 8. Thedie assembly of claim 7 wherein: the first thickness is in the range ofabout 50 μm to about 200 μm; and the second thickness is in the range ofabout 300 μm to about 1000 μm.
 9. The die assembly of claim 1, furthercomprising a plurality of through-stack interconnects extending throughthe stack of memory dies and electrically coupling the first logic diewith the second logic die.
 10. The die assembly of claim 1, furthercomprising a plurality of through-stack interconnects extending throughthe stack of memory dies and electrically coupling the second logic diewith individual memory dies of the stack of memory dies.
 11. Asemiconductor die assembly, comprising: a thermally conductive casing; afirst semiconductor die attached to a first portion of the thermallyconductive casing; a second semiconductor die attached to a secondportion of the thermally conductive casing separate from the firstportion; a stack of third semiconductor dies at least partially enclosedwithin the thermally conductive casing; and a plurality of through-stackinterconnects extending through the stack of third semiconductor dies,wherein— the stack of third semiconductor dies is disposed between thefirst and second semiconductor dies, and at least a portion of thethrough-stack interconnects electrically couple the first semiconductordie with the second semiconductor die.
 12. The die assembly of claim 11wherein another portion of the through-stack interconnects isfunctionally isolated from the first semiconductor die.
 13. The dieassembly of claim 11 wherein the portion of the through-stackinterconnects provides dedicated circuit paths between the first andsecond semiconductor dies.
 14. The die assembly of claim 11 wherein: thefirst semiconductor die includes a controller component; and the secondsemiconductor die includes a communication component operably coupled tothe controller component via the portion of the through-stackinterconnects.
 15. The die assembly of claim 11, further comprising apackage substrate carrying the first semiconductor die, wherein: thepackage substrate includes a plurality of package contacts; and thefirst semiconductor die includes a serializer/deserializer circuitcoupled between the package contacts and the portion of thethrough-stack interconnects.
 16. A semiconductor die assembly,comprising: a first logic die configured to receive a serial data streamand to deserialize the serial data stream into parallel data streams; astack of memory dies; and a second logic die carried by the stack ofmemory dies, wherein the second logic die is configured to receive theparallel data streams via the stack of memory dies.
 17. The die assemblyof claim 16 wherein the first logic die includes a memory controllerconfigured to receive the parallel data streams via the stack of memorydies.
 18. The die assembly of claim 16, further comprising a packagesubstrate, wherein the first logic die is configured to receive theserial data stream via the package substrate.
 19. The die assembly ofclaim 18 wherein the first logic die and the stack of memory dies areattached to the package substrate at different locations.
 20. The dieassembly of claim 18 wherein the first logic die is disposed between thepackage substrate and the of stack of memory dies. 21-34. (canceled) 35.A semiconductor system, comprising: a hybrid memory cube (HMC),including— a first logic die, a second logic die, a stack of memory diesdisposed between the first logic die and the second logic die, and athermally conductive casing attached to the second logic die andenclosing the stack of memory dies within an enclosure; and a driverelectrically coupled to the first logic die.